Providing additional bandwidth to layer 2/3 networks is often a slow process, involving building wavelengths directly over one or more dense wavelength division multiplexing (DWDM) systems. Improvements in the speed of wavelength delivery have been implemented, but those improvements have been limited by the non-flexible characteristics of the DWDM equipment. Because the final destination of additional bandwidth is not known until the need arises, it is not possible to deploy the required hardware and cabling until the actual provisioning time. That limitation can cause delays and expenses in meeting increased bandwidth demands.
Because of those limitations in adding bandwidth on demand, more bandwidth is often initially provisioned than is actually needed. That leads to extra capital cost, extra operations cost, and customer impact because of the inability of network providers to respond to short term spikes in demand.